Sewing-machine



(No Model.)

W.C. FRENCH;

SEWING MAGHINE.

Patented May 1', 1883.

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WILLIAM GIFRENOH, OF BOSTON, MASSACHUSETTS.

SEWING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 276,798, dated May 1, 1883. Application filed January 24, 1883. (No model.)

' To all whom it may concern Be it known that I, WILLIAM G. FRENCH, of Boston, in the county of Suffolk and State of Massachusetts, haveinvented a new and useful Improvement in Sewing-lllachines, which invention is fully set forth in the following specification, reference being bad tot-he accompanying drawings.

The object of my invention is to facilitate the removal of the material, garment, or work being stitched from the work-plate and presserfoot of the sewing-machine upon the completion of the stitching, or the change of position of the same on the work-plate from that in which one line of stitching is completed to the place of beginning another; and theinvention consists in the construction, combination, and arrangement of the divers devices embodied therein, as hereinafter more particularly and fully set forth and claimed. I

In the drawings, Figure 1 is a front elevation of the head of a sewing-machine, from which the cap or face plate is removed to show the arrangement therein of the presser-foot bar, its lifting-lever, and the needle-bar. Fig. 2 is a similar view, showing the cap or face-plate in position and the location and arrangement of the thread-guides, take'up, and tension device thereon. Fig. 3 is an enlarged detached vertical section taken on line :10 a, Fig. 2, and as viewed from the right of said figure, and shows the details of construction of the tension devices and their connection with the lever for raising thepresser-foot, with my invention embodied therein. Fig. 4 is a detached view similar to that of Fig. 3, but not enlarged, showing in sectional elevation the tension devices and a modification of the devices for conjoin tl y raising the presser-foot and actuating the tension-relieving spindle.

In operating sewing-machines which are not provided with devices for automatically slack 'ening the tension upon the thread, when aline of stitching is completed and a change of position ofthe work on the work-plate is required to commence another line of stitching, or for any other reason it becomes necessary to remove the work being stitched from its position upon the work-plate and beneath the presserfoot, itis necessary to notonly raise the presserfoot to relieve work from the spring-pressure thereof, but also to slacken the upper or needle thread connected with the work and held taut by the tension devices, such slackening of the thread being necessary in order to relieve the needle from the undue strain thereon which would result from an attempt to remove the work by drawing the attached thread through the eye of the needle, while it was so held taut, against the resistance of the tension devices, also to avoid unthreading the needle thereby by the overstrain and breakage of the thread, and thus delaying the stitching operation. The operator is therefore required, at every such change of the position of the work, to take hold of the thread and slacken the same by pulling it through the tension do vices to such an extent as to release the work from such thread strain and allow the same to be removed by drawing the attached thread freely through the eye of the needle without strain upon the needle. Unless such act of slackening be carefully performed, the needle is liable to be rendered useless by being sprung or broken, which often so happens, and the operation of stitching delayed.

By my invention the act of thus first pulling the thread by the hand of the operator through the tension devices against the resistance thereof is rendered unnecessary, the same result being attained by the single act of raising the presser-foot in the usual manner, the

' tension devices being so constructed, arranged and combined with the presser-foot devices that the one operation or act of lifting the presser-foot automatically or conjointlyrelaxes thetension upon the thread, and the act of lowering the foot'likewise restores the tension, all as will now be described.

Referring to Fig. 1, A represents the head of a sewing-machine of a well-known manufacture from which the cap or face-plate is removed. In said head are fitted to slide vertically the usual presser-foot bar, B, and needle-bar O, the former being pressed down upon the work-plate by a flat steel spring attached to the neck or arm of the machine at one end, while its yielding end D rests upon an arm attached'to bar B, as shown. Bar B isalso arranged to be raised through said arm by means of a cam-lever, E, pivoted at b, and shaped and arranged to raise said bar when ICC turned upon its pivot, and to hold the samein such elevated position, in the usual manner. In the side of cam-lever E is cut a curved groove, 01, of unequal depth, which forms an arc of a circle whose center is the axis of pivot 11. This groove isnot common in such liftinglevers, but is a part of. my improvement, the purpose of which will be hereinafter explained. Upon the cap or face-plate F, Fig. 2, are secured the usual thread-guides, a take-up, and a tension device, Gr. The construction of the latter in detail is shown in Fig. 3, consisting of a slotted tubular stud, a, secured at one end in cap F by being screwed into the same, as shown, and at its outer end is threaded to receive the tension-adjusting not (1. Upon this hollow stud are placed the usual friction-disks, e 0, between which the thread is held and compressed by the force of springf, when the latter is acted upon-by nut d, according to the degree of pressure required to secure the requisite tension upon the thread as it is drawn through said friction-disks. The details of the tension device thus far described are substantially the same in construction and arrangement as those in common use, except that stud c is not usually hollow or drilled through its entire length.

In carrying out my invention I make stud c hollow and insert therein a spindle, g, the inner end of which projects into the groove (1 of lever E, as shown, while near the opposite end of the spindle is firmly secured thereto a disk, h, (shown in elevation at h,) with its cross-bar t' centrally secured to spindle 9. When spindle g is inserted in stud c, the nut d and springfare'removed, when the inner end of spindle g is inserted in the outer and slotted end of stud 0, and being slid forward therein, the bar 2" passes along in the slots in said stud c. The disk 7L surrounds said stud, and is moved into contact with the front face ofthe outer friction-disk, c. The sprin g f is then placed upon stud c with its inner end in contact with disk h, and is followed by nut d, threaded upon the stud and against the spring, as shown. Thus the disk or flange h of spindle g is interposed between disk e and spring f, so that when the relieving-spindle g is forced outward in the manner to be described the disk 6 will be relieved from the pressure of said spring. When the lifting-lever E and the presser-foot are down, as shown, the groove a in said lever is of sufficient depth opposite the end of spindle g to allow the spindle to extend into the groove without touching the bottom thereof sufficiently to permit disk It to bear against the friction-disk 0 under the'full force of spring f, and without relieving the disks e of such compressive force at a time when the tension upon the thread should not be relaxed or interfered with by such relieving device.

The proper operation of my improvement is as follows: When it is applied to a machine in the manner described, and a line of stitching having been completed, and the operator being desirous to change thework upon or remove it from the work-plate 0, instead of seizing some portion of the thread between the tension and the needle-say at i, Fig. 2when no such devices are applied, and drawing it by hand against the resistance of the tension devices G, to produce sufficient slack thread to allow the party, between the eye of the needle and the work k, to be drawn upon by the removal of the work when the foot H is raised from the work-plate, as indicated by the dotted lines, without injury to the needle or breakage of the thread, simply raises the lever E, and thereby the presser-foot H, in the usual manner, and by that single act, through my improvements as connected with the lifting-lever F,

accomplishes the double purpose of raising thefoot from the work and releasing the tension on the thread at the same time, as when lever F is raised the diminishing depth of groove a, Fig. 3, brings the bottom thereof in contact with the end of spindleginserted therein, and gradually forces said spindle outward as the lever is turned upward, and its disk It against spring f, and thereby causes said spring to yield before said disk sufiiciently to entirely relieve the disks 0 from the pressure of the spring, thereby taking off the friction of said disks from the thread, and thus relaxing the tension thereon, so that the same may be drawn freely and harmlessly through the eye of the needle by the removal of the work with which-it is connected, as before stated; and by lowering the foot and restoring the pressure upon the work the tension upon the thread will at the same time and by the'same act of the operator be restored upon the thread.

It is obvious that the object of my invention may be accomplished by the'employment of two levers, E and E, as shown in Fig. 4, the former of which is connected with and operates the presser-foot,in the usual manner as described, while tlIelatter is connected directly IIO with and operates to relax the tension mechanism, as already described, said levers being so arranged in relation to each other that when the operator is actuating lever E he will without the bestowal of care or thought thereto also operate the tension-lever E, the proximity of said levers being such that only by the exercise of care can either be manipulated independently of the other. Such independent operation, however, is under certain conditions and for certain purposes desirable.

I am aware that devices for accomplishing the ultimate purpose or object of my invention have heretofore been embodied in sewingmachines, and I therefore confine my invention to the specific devices and combinations herein shown, described, and claimed.

I claim as myinvention- 1. In a tension mechanism'embodying the usual stud, a, friction wheels or disks 6, compressing-spring f, and adjusting-nut d, the

and arranged tointervene between said spring with its disk h, interposed between disk 0 and V f and disks 6, with means to automatically springf, and the lever E, having a groove, a, IO actuate the same, whereby the pressure of whereby said spindle is actuated,substantially spring f is removed from disks 0, substantially as and for the purposes specified. 5 as and for the purposes specified. WILLIAM C. FRENCH.

2. In combination with a tension mechan- Witnesses: ism embodying a stud, c, friction-disks e, EUGENE HUMPHREY,

spring f, and nut; d, the relieving-spindle g, D. W. G. HUMPHREY. 

